Objectives: We examined the association between combustible tobacco product use and e-cigarette use motivations in dual-product and exclusive e-cigarette users. Methods: Adult urban and rural Ohioan exclusive (N = 131) and dual e-cigarette users (N = 114) enrolled in a
cohort study rated 21 factors motivating e-cigarette use (eg, quitting combustible products) at baseline. Logistic regression stratified by user type and controlling for region (urban/rural) was used to evaluate associations between motivations for e-cigarette use and use of combustible tobacco
products within 18-months. Results: Among exclusive e-cigarette users, endorsing, "using e-cigarettes helps people quit smoking cigarettes" and "using an e-cigarette feels like smoking regular cigarettes" showed lower odds of using a combustible product at least some days per week within
18 months. Among dual-users, no e-cigarette use motivations emerged statistically significant in terms of combustible product use within 18 months, though a few e-cigarette motivations were borderline statistically significant. Conclusions: Among exclusive and dual e-cigarette users,
motivations related to the value of e-cigarettes as a cigarette substitute were associated with combustible product use at follow-up.

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